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    • Thanks Malich. For people like me with a less than ideal knowledge of the terminology, here's a glossary of terms used in relation to the NBN: http://www.nbnco.com.au/utility/glossary-of-terms.html
    • 384. Typical maximum distance from GPON to customer OLT is ~4km, though since it's based on loss (28dB) that can be tweaked out as far as ~20km in extraordinary circumstances (by minimising the number of joints, other services, etc on the fibre).
    • You seem to be assuming that a node cabinet can have an arbitrarily high number of connections to it. My understanding is that they are designed to take only up to a certain number of connections. I'd have thought that in a densely populated area, such as one with many flats/apartments, you'd need more cabinets per square kilometre.  
    • It's all shared somewhere. With cable, it's shared on the 'last mile' (to some degree) all the way back to the ISP. With ADSL it's shared on the link between the exchange & the ISP's network (or, in some cases, on the wholesale provider's connection to the exchange & on the connection between wholesaler & ISP). With fibre NBN, it's shared from the GPON/equivalent to the PoI, within the PoI (CVC virtual circuit, limited by PoI capacity & cost), and on the NNI (backhaul from the PoI to the ISP).   I think you might have a rose-coloured view of how these things are designed. At least for the forseeable future it makes no economic sense (& very little practical sense) to provide that sort of bandwidth all the way through, so there will always be a restriction somewhere. e.g. (assuming everybody's online & maxing out their connection) - the original* FTTP GPONs shared 2.488Gbps (downstream) across 32 customers i.e. ~77Mbps each. The ISAMs used so far for FTTN can share 8.192Gbps across 192 customers (i.e. ~43Mbps), but I believe were mostly installed with only 2.048Gbps worth of links (so, ~11Mbps). Either way, when it gets back to the PoI it's then restricted of the amount of CVC capacity (i.e. within the PoI) & NNI (PoI - ISP backhaul) capacity purchased by the ISP. You'd quickly go broke paying for 100% capacity, so they buy a % based on planned usage & cost - it varies from ISP to ISP, typically from ~50% to ~80%, so let's assume 70%. So if everyone decides to max out their connection at once, on fibre NBN you would reasonably expect ~54Mbps, on a fully-provisioned FTTN ISAM you would expect ~30Mbps, and on the FTTN ISAMs as installed you might expect ~8mbps. From what I read elsewhere & hear from friends still in the game, in the real world people on heavily-loaded GPONs & ISAMs are getting a little (or sometimes a lot) less than that - so I suspect my 70% assumption was a bit optimistic... (* There was a plan to start rolling out / update the original GPONs about now with newer XG/NG-GPONs having 10Gbps connection to the PoI i.e. 5x the capacity of the original GPONs. Don't know if that's still on the cards or not.) (edited for clarity & corrections)